a. Field of the Invention
The present invention pertains generally to wind turbines and more specifically to crossflow wind turbines having a plurality of stationary airfoils positioned about a rotor having a plurality of blades.
b. Description of the Background
Radial flow windmills that harness wind energy using a plurality of exposed blades have been used both privately and commercially for some time. These machines often have a high initial cost and have limited efficiency. Further, the exposed blades are hazardous to certain wildlife such as birds. In addition, radial windmills cannot normally be operated in very high wind conditions, as they often lack sufficient structural integrity and are not mechanically designed to prevent over-speeding.
Crossflow turbine wind machines, such as described in U.S. Pat. Nos. 6,015,258 to Taylor and U.S. Pat. No. 5,391,926 to Staley, et al., have been developed to address some of the limitations of the radial flow wind turbines. The crossflow turbine wind machine comprises a set of fixed stators that direct wind into a rotating turbine. One of the advantages to the crossflow turbine machine is the higher efficiencies that can be achieved, and they are less dangerous. Further, the structural integrity of the machine and the serviceability of the moving components are superior to that of a radial flow windmill.